Embargo; Invisible Mountain;; Discrimination series -P.32

And the Rounds froze Nousos' assets in their territory, supplied weapons to the discontented parties in a sphere of influence of Nouso to support a revolt,
strengthened the isolation policy towards Nousos and prohibited the exports of important resources to Nouso.

Neither the warships nor the tanks could work if they cannot import resources, in particular, the energy.
If neither the warships nor the tanks could work,
there's no way to protect Nouso from the hostility of the Rounds. They will be conquered and ruled like as other Triangles.